Ventilation system



Patented Nov. 8, 1949 VENTILATION SYSTEM Alexander Martin, Dedham, Mass., assgnor, by

mesme-assignments, to Westinghouse Electric Corporation, a corporation of Pennsylvania Application January 18, 1946, Serial No. 641,900

This invention relates to Ventilating systems, andrelates more particularly to Ventilating systems for work rooms in which the air is contaminated by gases such as fumes and smoke.

In some foundry rgoms there are a large number of small moulds which are so low that smoke and fumes exhaust therefrom into the foundry rooms well below the level of the attendants noses and eyes. For providing workable conditions in such rooms, it has been the practise in the past to Ventilate such rooms by forcing large volumes of outdoor air therethrough. For example, in a foundry room 30 x 30 with moulds 24 high, ithas been the practise to blow 27,000 cubic feet of air per minute through the room for providing adequate ventilation.

This invention provides high velocity air jets forming an air blanket, projected across an apparatus room below the head levels of attendants standing therein, which air blankets prevent the fumes and smoke from the moulds from rising to the head level of the attendants, and which entrain and exhaust the fumes and smoke. In

a foundry room in which it has been the practise in the past to supply 27,000 cubic feet of air per minute for providing adequate ventilation, this invention provides better conditions with only 6,000 cubic feet of air per minute.

An object of the invention is to reduce Vthe volume of air required for properly Ventilating a room in which gases such as fumes and smoke are exhausted at low levels.

The invention will now be described with reference to the drawing, of which:

Fig. 1 is a diagrammatic view of a foundri7 room equipped with a Ventilating system embodying this invention, the view being a plan view looking downwardly upon the room;

Fig. 2 is a diagrammatic side elevation of the foundry room of Fig. 1, and

Fig. 3 is an enlarged view of a portion of one of the air projection pipes of the system, the

, view being taken along the lines 3-3 of Fig. 1.

The foundry room illustrated has the large number of spaced, metal moulds I which, by way of example, may be 18" x 18 and 24 high. The foundry room may be 30 x 30. The two air compressors Il are, in the embodiment illustrated, located outside the room on opposite sides thereof, and their outlets I2 are connected through the sides of the room into the *air discharge pipesV I3, the inner faces of which extend parallel to each other and which contain the spaced apertures I4 forming air outlets for projecting high velocity, air jets therefrom as will 1 Claim. (Cl. 98-33) be described. The inlets I5 of the compressors are open to outdoor air.

The exhaust duct I6 extends across the room parallel to, and equally spaced from, the pipes I3, and is connected to the inlet Il of the exhaust fan I8. The outlet I9 of the fan I8 discharges into the atmosphere.

The exhaust hood 20 extendsover the upper, open end 2l of the duct I6, and has the sloping sides 22 which form with the outer edges of the duct, air entrance slots which may be about 2" Wide, and which extend the length of the exhaust duct and hood on both sides thereof.

The lower ends of the sloping sides 22 of the 55 hood 2|, terminate just above a plane extending through the axes of the apertures I4 of the pipes I3, whereby the air projected through the apertures moves in substantially a horizontal plane to the hood 2l to be drawn in under the go sides 22 thereof.

The apertures I 4 may be located about 40" from the iioor of the foundry room whereby the air blanket formed by the air projected from the apertures, extends well below the breathing g5 level of the workmen in the room.

In operation, each air compressor II may, by way of example, supply 1200 cubic feet of air per minute through the pipes I3 and apertures I4 into the room. The apertures may be onefourth inch in diameter and spaced 2" apart whereby the air may be projected therethrough at 18,000 feet per minute velocity. The high velocity jets of. air are projected towards the ,'exhaust hood 20 and are drawn therein through the previously described slots by the suction of the fan I8.

The fan I8 may be operated to draw in 6,000 cubic feet of air per minute at 500' per minute velocity through the said slots, the vo-lume of 4.0 6,000 cubic feet per minute being made up by per openings 25 or otherwise.

The air projected from the pipes I3, and drawn in at the hood 20 forms an air blanket which prevents the fumes and smoke from the moulds i0 from rising to the head level of workmen in the room, and which entrains the fumes and smoke and exhausts them through the hood from the room. The other air drawn in from overhead provides adequate ventilation.

While one embodiment of the invention has been described for the purpose of illustration,

enclosure at levels well below the head levels of` attendants standing therein, comprisingair discharge pipes extending crosswise said enclosure substantially the full widthzthereof at oppositeA sides of said containers, air-compressors'having" their outlets connected to said pipes soasto supply compressed air thereintof, saidlfpipeshaving in their sides which face said containers means for projecting air at high velocity there-y over, an exhaust hood extending crossWise said ,f

enclosure between said pipes, a fan having its inlet connected to said hood,.said hood having in'itssides whichk face said pipes air inlet'means forv drawing'thereinto at4 high Velocity the air projected from said pipes, saidv air projecting means in said pipes and said air inlet means in said hood extendingfabove said containers but below the head levels of said attendants standing in said enclosure, said enclosure having an air inlet opening therein above said pipes and hood, said fan having a capacity greater than that of said compressors whereby some of the air drawn from said enclosure through said hood is drawn into said enclosure through said air inlet opening.

ALEXANDER MARTIN.

REFERENCES CITED The following references are of record in the file o'this patent:

UNITED 'STATES PATENTS Number Name Date 666,859 Bosley Jan. 29, 1901 1;138,470 Hackney May 4, 1915 1,254,725 Pennock Jan. 29, 1918 1,539,973 Truxal June 2, 1925 2,000,637 Hatch May 7, 1935 2,073,744 Henney Mar. 16,-' 1937 2,184,484 Bojner Dec. 2611939 2,262,243 Lord Nov.` 11,-,1941 2,319,703 Olson May 18, 1943 FOREIGN YPATENIS Number Country Date 7,814 Norway Dec.' 4, 1899 

